The present invention relates to a pneumatic tire and a measuring method of a tread wear amount thereof, more specifically, to a pneumatic tire rendered capable of readily measuring a tread wear amount thereof, and a measuring method of the tread wear amount.
Heretofore, measurement of a tread wear amount of a pneumatic tire has been performed by an operator by means of directly measuring a depth of a groove on a tread surface using a measuring instrument such as a caliper. Accordingly, there has been a problem that measured values of the tread wear amounts may vary due to individual differences of operators.
As a remedy for the above-described problem, a technique of measuring the tread wear amount by use of a laser displacement gauge has been proposed. By continuously detecting distances to a tread surface including main grooves while moving the laser displacement gauge over the tread surface in a width direction of the tire, residual depths of the main grooves are computed, whereby the tread wear amount is automatically measured.
However, an apparatus for measuring the tread wear amount as described above requires an aligning mechanism in order to move the laser displacement gauge with precision. This has incurred a problem such as a complex structure, a high price and onerous maintenance. For this reason, it has been difficult to introduce such apparatus, and further improvements have been expected.